Heat-sensitive recording material

A full-color heat-sensitive recording material comprising:

• a support;
• a heat-sensitive recording layer that color-develops to yellow, provided on said support;
• a heat-sensitive recording layer that color-develops to cyan, provided on said heat-sensitive recording layer that color-develops to yellow;
• and
• a heat-sensitive recording layer that color-develops to magenta, provided on said heat-sensitive recording layer that color-develops to cyan,
• wherein each of said heat-sensitive recording layers includes:
• at least one of a diazo compound and a diazonium salt;
• and a coupler compound that reacts with said at least one of a diazo compound and a diazonium salt for developing color,
• said at least one of a diazo compound and a diazonium salt in said heat-sensitive recording layer that color-develops to yellow including a diazo compound of the following general formula (I):
• in which:
• R1, R2, R3 and R4 each independently represent a group selected from the group consisting of a hydrogen atom, halogen atoms, alkyl groups, aryl groups, —OR51, —SR51, —COOR51, —CONR51R52, —SO2R51, —SO2NR51R52, —COR51, —NR51R52, a nitro group and a cyano group;
• R51 and R52 each independently represent a group selected from the group consisting of a hydrogen atom, alkyl groups, aryl groups and acyl groups;
• R5 represents a group selected from the group consisting of a hydrogen atom, alkyl groups, aryl groups, —COOR53, —CONR53R54, —SO2R53, —SO2NR53R54 and —COR53;
• and R53 and R54 each independently represent a group selected from the group consisting of a hydrogen atom, alkyl groups, aryl groups and acyl groups,
• said heat-sensitive recording layer that color-develops to cyan including at least one of diazonium salts of the following general formulae (A) to (C):
• wherein:
• X− represents an anion;
• in the general formula (A), Ar represents a substituted or unsubstituted aryl group, R17 and R18 each independently represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, and R17 and R18 may be the same and may be different from each other;
• in the general formula (B), R20, R21 and R22 each independently represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, R20, R21 and R22 may be the same and may be different from each other, Y represents a hydrogen atom or OR19, and R19 represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group;
• and in the general formula (C), R23 and R24 each independently represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, and R23 and R24 may be the same and may be different from each other, and
• said at least one of a diazo compound and a diazonium salt in said heat-sensitive recording layer that color-develops to magenta including a diazo compound of the following general formula (I):
• in which:
• R31 and R32 each independently represent a hydrogen atom, alkyl group or aryl group;
• R33 and R34 each independently represent a hydrogen atom, alkyl group, aryl group or halogen atom;
• R35, R36, R37, R38 and R39 each independently represent a hydrogen atom, alkyl group, aryl group, halogen atom, alkoxy group, aryloxy group, alkoxycarbonyl group, acyloxy group, carbamoyl group, amide group, cyano group, alkylthio group, arylthio group, alkylsulfonyl group, arylsulfonyl group;
• at least one of R35, R36, R37, R38 and R39 represents a halogen atom;
• and X− represents an anion.